Currency exchange rates across the 21-country European Union are prompting international travelers to look elsewhere this summer.

"More people are traveling internationally, but where they're going is different," says Amy Ziff of Travelocity, the online travel agency.

Summer bookings for countries where the euro is used — such as Spain, France and Italy — are 15% lower than last year, while bookings are up 16% for Eastern European countries that don't use the euro, she says.

American Express's international travel bookings for this summer so far are ahead of last year, with significant growth in China, South America, Hong Kong, Moscow and St. Petersburg, Russia, says Mona Hamouly, spokeswoman for American Express Travel.

Many people who want to leave the USA for a week or so are going to countries where the dollar buys more.

The Caribbean's share of Travelocity's summer bookings is up 15%, the share for South America — including hotspots such as Buenos Aires — is up 13%, and Mexico's share is up 47%.

Bookings for the first three months of the year are already 10% higher than this time last year, he says.

"Mexico offers some of the things that Europe offers," he says. "Another culture, artists, food, music, and also sun and beach. It's a very nice vacation with a budget that they can afford."

Interest in international trips this summer is being buoyed by the swell in U.S. passport holders.

About 88 million people now hold a passport, according to the U.S. State Department, 19% more than last year.

Western Europe still attracts the most Americans each summer, and it remains popular. American Express says that despite the currency rates, it's seeing double-digit, year-over-year gains in trips to Zurich, Geneva and the rest of Switzerland; Pisa, Italy; and Lisbon, Portugal.

"I have heard a lot of grumbling about the U.S. dollar, but it is not stopping them. Travel has become a lifestyle," says Pam Edwartoski of the Carlson Wagonlit travel agency in Troy, Mich.

Many Europe-bound travelers, however, are watching their wallets by being flexible on destinations and the dates of travel to get better rates, she says. They're also:

•Shortening their stay. The average international trip booked this summer is 12 days, which is 5% shorter than last year, Ziff says.

•Booking an escorted tour. More travelers who buy European tours are opting for the most structured, escorted tour because they include more things, says Bob Whitley, president of the U.S. Tour Operators Association.

"If you pay $4,000 for 14 days in Europe, that's your cost. Everything's included — even your tickets to the Louvre," Whitley says. "The only addition is if you want to buy a cuckoo clock or Burberry coat."

•Booking a cruise. Sales of river cruises, whether the Danube in Germany or the Yangtze in China, are soaring this summer, Whitley says. Americans like the fact that prices typically include food, wine and stops in towns and villages, so they won't be subject to currency fluctuations.

•Planning in advance. Mike Weingart of Carlson Wagonlit Travel in Houston says more people are booking hotel rooms, tours and Rail Europe tickets in advance so they can lock in the price in dollars.

Jose Ramon Garcia of Rio Rico, Ariz., says he booked his tickets to Spain in March to snag the best fare and bought $1,500 worth of euros to lock in a favorable rate and avoid ATMs in Europe.

"I figure that it will be very expensive to live for two weeks, but this is not a compelling reason to cancel a trip to Europe," he says.

But even knowing the best money-saving strategies isn't persuading everyone to go abroad.

Of 200 Carlson Wagonlit agents polled, 46% expect international bookings to fall this summer vs. last summer. Just 19% of agents say they expect bookings to surpass last year's levels.

Whitley's group, the U.S. Tour Operators Association, which has about 350 members that sell international travel, expects international trips to be down by as much as 10%, he says. And 66% of 6,678 adults contacted in February for an AOL Travel-Zogby International poll said they plan to stay in the USA this summer.

Lupe de la Torre of Chicago, a city worker, had dreamed of celebrating her 40th birthday in Italy with a 10-day trip to Venice, Florence and Rome. But a price of about $4,500 per person — coupled with unfavorable exchange rates for souvenirs and incidentals — made the cost for her and her son "outrageous."

Now, she's leaning toward a trip to Albuquerque centered on a hot-air-balloon ride she's also wanted to take. She'll save money partly by going away for a long weekend instead of 10 days.

"I like to do something different every year," she says. "It will still be special."

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Look south, not east: The dollar is still struggling against the euro.

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